1. Field of the Invention
The present invention relates to a liquid crystal device, and more particularly, to a liquid crystal device having a liquid crystal layer that contains a polymer.
2. Description of the Related Art
Liquid crystal devices are devices which include a liquid crystal layer provided between a pair of substrates and which display letters, numbers, figures, pictures, and the like using electro-optical effects. As an example of a driving mode of the liquid crystal devices, a TN (Twisted Nematic) mode, an STN (Super Twisted Nematic) mode, a VA (Vertical Alignment) mode, an OCB (Optically Compensated Birefringence) mode, an IPS (In-Plane Switching) mode, and an FFS (Fringe Field Switching) mode are known.
In recent years, the liquid crystal devices using those driving modes have been manufactured for use not only as a liquid crystal device for a desktop personal computer but also as a large-screen liquid crystal device for a liquid crystal television. Moreover, development on a compact liquid crystal device applied to a cellular phone and the like has also seen progress.
Liquid crystal devices of this kind are classified into two types: one is a type (simple matrix type) in which a voltage is selectively applied to electrodes for pixel formation which are formed on each substrate, thus driving a predetermined pixel, and the other is a type (active matrix type) in which various kinds of electrodes and switching elements (active elements) such as thin-film transistors (TFTs) for pixel switching are formed on one substrate, and a predetermined pixel is driven by selecting the active elements. In particular, the latter, i.e., the active matrix-type liquid crystal devices are the major liquid crystal devices since they have excellent performance, for example, in contrast performance and fast display performance.
From a viewpoint that the liquid crystal device is expected to be used as a display device for the liquid crystal television, there is a demand for fast-switching (reduction in response time) to be used for displaying moving pictures in sports programs and other similar programs. As one strategy to meet this demand, the use of low-viscosity liquid crystal compositions can be considered. As such liquid crystal compositions, nematic liquid crystal having fluorine substituted components has been developed in place of nematic liquid crystal having cyano substituted components which has been used in STN liquid crystals. The nematic liquid crystal having fluorine substituted components has high specific resistance as compared with the nematic liquid crystal having cyano substituted components and is thus considered as liquid crystal having high reliability and causing less unevenness in displayed images.
As a strategy to achieve a faster-switching, other than the use of low-viscosity liquid crystal compositions, JP2003-279995A, for example, proposes the use of polymer-stabilized liquid crystal compositions.